by Nils Osmar. February 3, 2022
Medcram is one of my favorite science and medicine related channels – always interesting and thought-provoking. In this episode, the focus is on light exposure with a close examination of:
- the importance of exposure to light from the sun (the quality of which changes as the day moves on)
- the production of melatonin and cortisol
- circadian rhythms and sun exposure
- the increased risk of cancer due to circadian disruption
- sun exposure as a factor in immune health (important in the current pandemic)
- and the benefits and drawbacks of oxidative stress as they relate to mitochondrial health.
Some key points:
- Melatonin is essential to immune health and longevity. This part was news to me: Only 5 percent of the body’s melatonin is produced by the pineal gland. 95 percent of our melatonin is produced by the mitochondria.
- A recent study showed that light therapy (correlated to the time of day) was effective in alleviating bipolar depression.
- One implication is that simply supplementing with vitamin D may not be sufficient for making up for a lack of sun exposure.
- There can be benefits to reading actual physical books at night (by lamplight in a darkened room) (when we want to limit our light exposure) rather than reading ebooks on a device.
“You want to have bright light exposure early in the morning when you’re getting up to anchor the circadian rhythm and make sure your cortisol levels are coming up at the right time. We need bright light to activate photoreceptors in the retina. If you use a light box be 11-15″ from it.”
- I’ve gotten into the habit of watching movies or television at night. I’m going to try segueing into reading “real” books instead, by lamplight in a darkened room, perhaps with a one of the red lights from my red light therapy booth switched on nearby.
- I have a light box; this video is a good reminder to use it in the morning, which I don’t always think about doing.